Has anyone developed an awful rash while taking Focalin XR and being out in the hot sun? I am on?

... Lexapro 20mg and Focalin XR 15mg. I started 10mg of Lexapro in February 2016, and vacationed in sunny Florida for a week and a half with no issues. I bumped up to 20 mg of Lexapro then after about 2-3 weeks I introduced 10mg of Focalin XR, and then again 3 weeks later bumped up to 20mg focalin XR, which I found to be to wrong for me so we lowered to 15mg Focalin which seems to work okay in conjunction with the Lexapro 20mg. 2weeks ago I developed a rash on my back, chest, neck, arms and legs. I then had night sweats and painful joints extremely fatigued. I felt like this was the end for me, never had I felt so bad. My Dr said it didn't look like a medication side effect that it may be a viral infection. The rash lasted a week after sleeping days and nights away I eventually felt and looked better. Well the rash has come back along with painful ankles, knees, hips, and rotators, last night I had night sweats each day looks worse the dr doesn't know what it is. Both times before the rash starts I have been outside in direct sunlight working, it has been very hot. Is this what happens with photosensitivity? I was also recently diagnosed with Sjögren's syndrome.